U.S. patent number 7,591,686 [Application Number 11/379,100] was granted by the patent office on 2009-09-22 for communications connectors with jackwire contacts and printed circuit boards.
This patent grant is currently assigned to CommScope, Inc. of North Carolina. Invention is credited to Michael Walter Canning, Thomas Ellis, Ron Guelden, Troy Long.
United States Patent |
7,591,686 |
Ellis , et al. |
September 22, 2009 |
**Please see images for:
( Certificate of Correction ) ** |
Communications connectors with jackwire contacts and printed
circuit boards
Abstract
Communications connectors having a plurality of signal carrying
paths include a printed circuit board and a plurality of contacts.
The printed circuit board has a plurality of contact pads, a
plurality of output terminals, and a plurality of conductive paths
that electrically connect at least some of the plurality of contact
pads to respective ones of the plurality of output terminals. The
contacts each have a plug contact region. In these connectors, a
first of the plurality of signal carrying paths extends from the
plug contact region of a first of the plurality of contacts to a
first of the plurality of output terminals through a first of the
contact pads and a first of the conductive paths.
Inventors: |
Ellis; Thomas (Dallas, TX),
Canning; Michael Walter (Plano, TX), Long; Troy (Omaha,
NE), Guelden; Ron (Omaha, NE) |
Assignee: |
CommScope, Inc. of North
Carolina (Hickory, NC)
|
Family
ID: |
38512690 |
Appl.
No.: |
11/379,100 |
Filed: |
April 18, 2006 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20070243728 A1 |
Oct 18, 2007 |
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Current U.S.
Class: |
439/676;
439/941 |
Current CPC
Class: |
H01R
13/6658 (20130101); H01R 13/6467 (20130101); Y10S
439/941 (20130101) |
Current International
Class: |
H01R
24/00 (20060101) |
Field of
Search: |
;439/676,941,82 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 982 815 |
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Mar 2000 |
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EP |
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2 823 606 |
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Oct 2002 |
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FR |
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Other References
International Search Report and Written Opinion for
PCt/US2007/008867; Oct. 5, 2007. cited by other.
|
Primary Examiner: Nguyen; Truc T
Assistant Examiner: Chung-Trans; Xuong M
Attorney, Agent or Firm: Myers Bigel Sibley &
Sajovec
Claims
That which is claimed is:
1. A communications connector having a plurality of signal carrying
paths, the communications connector comprising: a printed circuit
board that includes a plurality of openings in a first surface
thereof, a plurality of contact pads that are spaced apart from the
plurality of openings, a plurality of output terminals, and a
plurality of conductive paths that connect at least some of the
plurality of contact pads to respective ones of the plurality of
output terminals; and a plurality of contacts, each contact having
a plug contact region, a pad contact region that is in an
elastically mobile region of each respective contact and that is
arranged to mate with a respective one of the plurality of contact
pads and a termination end that is mounted in a respective one of
the plurality of openings in the first surface of the printed
circuit board, wherein a first of the plurality of signal carrying
paths extends from the plug contact region of a first of the
plurality of contacts to a first of the plurality of output
terminals through a first of the contact pads and a first of the
conductive paths.
2. The communications connector of claim 1, wherein each of the
plurality of contact pads extends from a side edge of the printed
circuit board onto a second surface of the printed circuit board
that is opposite the first surface.
3. The communications connector of claim 2, wherein at least some
of the plurality of contact pads comprise raised contact pads that
extend above the second surface of the printed circuit board.
4. The communications connector of claim 3, wherein each of the
raised contact pads comprises a nail that is inserted into the
printed circuit board.
5. The communications connector of claim 1, wherein each of the
plurality of contacts wraps around the printed circuit board to
extend above a second surface of the printed circuit board that is
opposite the first surface.
6. The communications connector of claim 5, wherein each of the
plurality of contact pads are on at least the second surface of the
printed circuit board, and wherein each of the plurality of
contacts includes an undulation region that is configured to mate
with a respective one of the plurality of contact pads.
7. The communications connector of claim 5, wherein each of the
plurality of contact pads are on at least the top surface of the
printed circuit board, and wherein an open area is provided between
each contact and the top portion of a forward edge of the printed
circuit board that each contact wraps around.
8. The communications connector of claim 1, wherein the pad contact
region on each contact is between the termination end of the
contact and the plug contact region.
9. The communications connector of claim 1, wherein the pad contact
region on each contact is between the plug contact region and a
free end of each contact.
10. The communications connector of claim 1, wherein the pad
contact region is within the plug contact region.
11. The communications connector of claim 1, wherein the plurality
of contacts comprises first, second, third, fourth, fifth, sixth,
seventh and eighth contacts, wherein the fourth and fifth contacts
comprise a first contact pair for carrying a first balanced signal,
the first and second contacts comprise a second contact pair for
carrying a second balanced signal, the third and sixth contacts
comprise a third contact pair for carrying a third balanced signal,
the seventh and eighth contacts comprise a fourth contact pair for
carrying a fourth balanced signal, wherein the plug contact regions
of the first through eighth contacts are arranged in a generally
side-by-side relationship in consecutive order, and wherein at
least one of first, second third and/or fourth contact pairs
includes a crossover.
12. The communications connector of claim 11, wherein the third
contact pair includes a crossover.
13. The communications connector of claim 11, wherein the first,
second and fourth contact pairs each include a crossover.
14. The communications connector of claim 1, wherein the printed
circuit board includes a compensation circuit that is electrically
connected by respective conductive traces to metal plating provided
in at least two of the plurality of openings in the first surface
of the printed circuit board.
15. The communications connector of claim 1, the communications
connector further comprising a housing, and wherein each of the
plurality of contacts includes a mounted end that is fixed in the
housing.
16. The communications connector of claim 1, wherein the plurality
of conductive paths comprises first, second, third, fourth, fifth,
sixth, seventh and eighth conductive paths, wherein the fourth and
fifth conductive paths comprise a first pair for carrying a first
balanced signal, the first and second conductive paths comprise a
second pair for carrying a second balanced signal, the third and
sixth conductive paths comprise a third pair for carrying a third
balanced signal, the seventh and eighth conductive paths comprise a
fourth pair for carrying a fourth balanced signal, and wherein the
third and fifth conductive paths at least partially run adjacent
each other to form an inductive crosstalk compensation stage.
17. The communications connector of claim 1, wherein each of the
plurality of contacts includes an elastically mobile region that
extends from a portion of the contact adjacent a bottom of the
forward edge of the printed circuit board through a free end of the
contact that is positioned above a top surface of the printed
circuit board.
18. A communications connector, comprising: a printed circuit board
that includes a plurality of signal carrying paths that connect a
plurality of input terminals of the communications connector to
respective of a plurality of output terminals; a plurality of
contacts, each of the plurality of contacts having a mounted end at
which the contact is mounted within the communications connector
and a plug contact region that comprises one of the plurality of
input terminals; wherein at least some of the mounted ends comprise
branches off of the signal carrying paths; wherein the mounted end
of each contact is mounted in a respective one of a plurality of
metal-plated holes in the printed circuit board; and wherein the
printed circuit board further comprises a plurality of contact
pads, and wherein each of the plurality of contacts further
includes a pad contact region that is configured to mate with a
respective one of the contact pads.
19. The communications connector of claim 18, wherein the pad
contact region of each contact is between the mounted end of the
contact and the plug contact region of the contact.
20. The communications connector of claim 18, wherein each of the
plurality of contact pads extends from a side edge of the printed
circuit board onto a top surface of the printed circuit board.
21. The communications connector of claim 18, wherein each of the
plurality of contacts further includes a free end, and wherein the
pad contact region is between the plug contact region of the
contact and the free end of the contact.
22. The communications connector of claim 18, wherein the mounted
end of each contact is mounted on a first surface of the printed
circuit board, and wherein each contact wraps around the printed
circuit board to extend above a second surface of the printed
circuit board that is opposite the first side.
23. The communications connector of claim 18, wherein at least one
of the plurality of contact pads comprises a nail that is inserted
into the printed circuit board.
24. The communications connector of claim 18, the communications
connector further comprising a housing, and wherein the mounted end
of each contact is fixed in the housing.
25. The communications connector of claim 18, wherein each of the
plurality of contacts are disposed in a parallel side-by-side
relationship with respect to the other of the plurality of contacts
over at least half of the contacts length.
26. The communications connector of claim 18, wherein each of the
plurality of contacts includes a free end, and wherein the free
ends of at least two adjacent ones of the plurality of contacts are
staggered with respect to each other to increase the distance
between the free ends of the at least two adjacent ones of the
plurality of contacts.
27. The communications connector of claim 18, wherein each of the
plurality of contacts wraps around a forward edge of the printed
circuit board and is free-floating adjacent the forward edge of the
printed circuit board.
28. A modular jack, comprising: a printed circuit board that
includes a plurality of contact pads at or adjacent a forward edge
of the printed circuit board, a plurality of output terminals, and
a plurality of conductive paths that electrically connect at least
some of the plurality of contact pads to respective ones of the
plurality of output terminals; and a plurality of contacts, each
contact having a mounted end mounted in a first surface of the
printed circuit board, a free end and a middle portion extending
between the mounted end and the free end, wherein the middle
portion wraps around the forward edge of the printed circuit board
to extend above a second surface of the printed circuit board that
is opposite the first surface: wherein each of the plurality of
contact pads are mounted to make electrical contact with the middle
portion of respective ones of the plurality of contacts when a plug
is in place in the modular jack.
29. The modular jack of claim 28, wherein at least some of the
plurality of contact pads comprise raised contact pads that extend
above a top surface of the printed circuit board.
30. The modular jack of claim 28, wherein the mounted end of each
of the plurality of contacts is mounted in respective ones of a
plurality of metal-plated holes in the printed circuit board.
31. The modular jack of claim 30, wherein the middle portion of
each contact includes a plug contact region, and wherein the
plurality of contact pads make electrical contact with the
respective ones of the plurality of contacts in between the plug
contact region of each contact and the mounted end of each
contact.
32. The modular jack of claim 30, wherein each of the plurality of
contacts is free-floating adjacent the forward edge of the printed
circuit board.
33. A communications connector having at least first, second, third
and fourth signal carrying paths, the communications connector
comprising: a printed circuit board that includes a first contact
pad, a second contact pad, a third contact pad and a fourth contact
pad, a first output terminal that is electrically connected to the
first contact pad via a first interconnection path, a second output
terminal that is electrically connected to the second contact pad
via a second interconnection path, a third output terminal that is
electrically connected to the third contact pad via a third
interconnection path, and a fourth output terminal that is
electrically connected to the fourth contact pad via a fourth
interconnection path; a first contact, the first contact having a
mounted end, a first pad contact region and a first plug contact
region, wherein the first signal carrying path extends from the
first plug contact region to the first output terminal through the
first pad contact region and the first interconnection path; a
second contact, the second contact having a second mounted end, a
second pad contact region and a second plug contact region, wherein
the second signal carrying path extends from the second plug
contact region to the second output terminal through the second pad
contact region and the second interconnection path; a third
contact, the third contact having a third mounted end, a third pad
contact region and a third plug contact region, wherein the third
signal carrying path extends from the third plug contact region to
the third output terminal through the third pad contact region and
the third interconnection path; and a fourth contact, the fourth
contact having a fourth mounted end, a fourth pad contact region
and a fourth plug contact region, wherein the fourth signal
carrying path extends from the fourth plug contact region to the
fourth output terminal through the fourth pad contact region and
the fourth interconnection path.
34. The communications connector of claim 33, wherein the first
mounted end region is outside the first signal carrying path but
electrically connected to the first signal carrying path, wherein
the second mounted end is outside the second signal carrying path
but electrically connected to the second signal carrying path,
wherein the third mounted end is outside the third signal carrying
path but electrically connected to the third signal carrying path,
wherein the fourth mounted end is outside the fourth signal
carrying path but electrically connected to the fourth signal
carrying path.
Description
FIELD OF THE INVENTION
The present invention relates generally to communication connectors
and, more particularly, to communications connectors that include
jackwire contacts and a printed circuit board.
BACKGROUND
In an electrical communications system, it is sometimes
advantageous to transmit information signals (e.g., video, audio,
data) over a pair of wires (hereinafter "wire pair" or
"differential pair") rather than a single wire. The signals
transmitted on each wire of the wire pair have equal magnitudes,
but opposite phases, and the information signal is embedded as the
voltage difference between the signals carried on the two wires.
This transmission technique is generally referred to as "balanced"
transmission. When signals are transmitted over wires, electrical
noise from external sources such as lightning, automobile spark
plugs, radio stations, etc. may be picked up by the wire, degrading
the quality of the signal carried by the wire. With balanced
transmission techniques, each wire in a wire-pair often picks up
approximately the same amount of noise from these external sources.
Because approximately an equal amount of noise is added to the
signals carried by both wires of the wire pair, the information
signal is typically not disturbed, as the information signal is
extracted by taking the difference of the signals carried on the
two wires of the differential pair, and thus the noise signal is
cancelled out by the subtraction process.
Many communications systems include a plurality of differential
wire pairs. For example, the typical telephone line includes two
differential wire pairs (i.e., a total of four wires), where one
wire pair carries the voice signal that travels in one direction
(i.e., the voice signal from the calling party to the called party)
and the other wire pair carries the voice signal traveling in the
opposite direction (i.e., from the called party to the calling
party). Similarly, high speed communications systems that are used
to connect computers and/or other processing devices to local area
networks and/or to external networks such as the Internet typically
include four differential wire pairs. In such systems, the wires of
the multiple differential pairs are usually bundled together within
a cable and thus necessarily extend in the same direction for some
distance. Unfortunately, when multiple differential pairs are
bunched closely together, another type of noise referred to as
"crosstalk" may arise.
"Crosstalk" refers to signal energy from a wire of one differential
pair that is picked up by a wire of another differential pair in
the communications system. Typically, a variety of techniques are
used to reduce crosstalk in communications systems such as, for
example, tightly twisting the wires in a cable so that each wire in
the cable picks up approximately equal amounts of signal energy
from the two wires of each of the other differential pairs included
in the cable. If this condition can be maintained, then the
crosstalk noise may be significantly reduced, as the wires of each
differential pair carry equal magnitude, but opposite phase signals
such that the crosstalk added by the two wires of a differential
pair onto the other wires in the cable tends to cancel out. While
such twisting of the wires and/or various other known techniques
may substantially reduce crosstalk in cables, most communications
systems include both cables and communications connectors that
interconnect the cables and/or connect the cables to computer
hardware. Unfortunately, the communications connector
configurations that were adopted years ago generally did not
maintain the wires of each differential pair a uniform distance
from the wires of the other differential pairs in the connector
hardware. Moreover, in order to maintain backward compatibility
with connector hardware that is already in place in homes and
office buildings throughout the world, the connector configurations
have, for the most part, not been changed. As a result, many
current connector designs generally introduce some amount of
crosstalk.
FIG. 1 depicts an exemplary electrical communications system in
which crosstalk is likely to occur. As shown in FIG. 1, a computer
1 is connected by a cable 2 that contains a plurality (typically
four) wire-pairs to a modular wall jack 5 that is mounted in a wall
plate 9. The cable 2 is a patch cord that includes a modular plug
3, 3' at each end thereof. Modular plug 3 inserts into a modular
jack (not pictured in FIG. 1) provided in the back of the computer
1, and modular plug 3' inserts into an opening 6 in the front side
of the modular jack 5, wherein the blades of the plug 3' mate with
respective contacts of the jack 5. In this manner, electrical
signals may be communicated from the computer 1 to the modular jack
5. The modular jack 5 includes a connector assembly 7 at the back
end thereof that receives and holds wires from a second cable 8
that are individually pressed into slots in the connector assembly
7 to make mechanical and electrical connection. The second cable 8
may connect the computer 1 to, for example, network equipment
and/or the Internet.
Pursuant to certain industry standards (e.g., the TIA/EIA-568-B.2-1
standard approved Jun. 20, 2002 by the Telecommunications Industry
Association), the communication system of FIG. 1 may include a
total of eight wires (four differential pairs). These standards
also specify that at the plug-jack mating point the eight wires are
aligned in a row, with the four differential pairs specified as
depicted in FIG. 2. As shown in FIG. 2, in at least the connection
region where the contacts of the modular plug 3' (see FIG. 1) mate
with the contacts of the modular jack 5, the wires of the
differential pairs are not equidistant from the wires of the other
differential pairs. By way of example, wire 2 (of pair 2) is closer
to wire 3 (of pair 3) than is wire 1 (of pair 2) to wire 3.
Consequently, differential capacitive and/or inductive couplings
occurs between the wires of pairs 2 and 3 that generate near-end
crosstalk (NEXT) (i.e., the crosstalk measured at an input location
corresponding to a source at the same location) as well as far-end
crosstalk (FEXT) (i.e., the crosstalk measured at the output
location corresponding to a source at the input location). This
crosstalk is an undesirable signal that interferes with the
information signal. Similar differential coupling occurs with
respect to the other wire pairs in the modular plug 3' and the
modular jack 5.
U.S. Pat. No. 5,997,358 to Adriaenssens et al. (hereinafter "the
'358 patent") describes a two-stage scheme for compensating NEXT
for a plug-jack combination. The entire contents of the '358 patent
are hereby incorporated herein by reference as if set forth fully
herein, as are the contents of U.S. Pat. Nos. 5,915,989; 6,042,427;
6,050,843; and 6,270,381. Connectors described in the '358 patent
can reduce the internal NEXT (original crosstalk) between the
electrical wire pairs of a modular plug by adding a fabricated or
artificial crosstalk, usually in the jack, thereby canceling or
reducing the overall crosstalk for the plug-jack combination. The
fabricated crosstalk is referred to herein as a compensation
crosstalk. One method of reducing NEXT disclosed in the '358 patent
is by twice crossing the path of one of the differential pairs
within the connector relative to the path of another differential
pair within the connector, thereby providing two stages of NEXT
compensation. Alternatively, the first and/or second compensation
stages can be implemented using discrete components and/or by
inducing desired capacitive and/or inductive coupling without
actually crossing wire paths. The multi-stage (i.e., two or more)
compensation schemes disclosed in the '358 patent can be more
efficient at reducing the NEXT than schemes in which the
compensation is added at a single stage, especially when the second
and subsequent stages of compensation include a time delay that is
selected and/or controlled to account for differences in phase
between the offending and compensating crosstalk signals. This type
of arrangement can include capacitive and/or inductive elements
that introduce multi-stage crosstalk compensation, and is typically
employed in jack lead frames and printed circuit board structures
within jacks. These configurations can allow connectors to meet
"Category 6" performance standards set forth in TIA/ETA 568B.2-1
standard, which are primary component standards for mated plugs and
jacks for transmission frequencies up to 250 MHz.
SUMMARY
Pursuant to embodiments of the present invention, communications
connectors having a plurality of signal carrying paths are
provided. These communications connectors include a printed circuit
board. The printed circuit board has a plurality of contact pads, a
plurality of output terminals, and a plurality of conductive paths
that connect at least some of the plurality of contact pads to
respective ones of the plurality of output terminals. The
connectors also include a plurality of contacts, each of which has
a plug contact region. In these connectors, a first of the
plurality of signal carrying paths extends from the plug contact
region of a first of the plurality of contacts to a first of the
plurality of output terminals through a first of the contact pads
and a first of the conductive paths.
In some embodiments, each of the plurality of contact pads may
extend from an edge of the printed circuit board onto a top surface
of the printed circuit board. At least some of the contact pads may
be raised contact pads that extend above a top surface of the
printed circuit board, such as, for example, a nail that is
inserted into the printed circuit board. The contacts of the
connector may include a contact termination that is mounted in an
opening in a first surface of the printed circuit board, and each
of the contacts may wrap around the printed circuit board to extend
above a second surface of the printed circuit board that is
opposite the first surface.
In certain embodiments, each of the contact pads may be on the top
surface of the printed circuit board, and each of the contacts may
include an undulation region that is configured to mate with a
respective one of the contact pads. The contacts include a pad
contact region that is arranged to mate with a respective one of
the contact pads. In some embodiments, the pad contact region is in
between a mounted end of the contact and the plug contact region.
In other embodiments, the pad contact region is in between the plug
contact region and a free end of the contact. The pad contact
region may also be within the plug contact region.
In certain specific embodiments, first through eighth contacts are
provided, where the fourth and fifth contacts comprise a first
contact pair for carrying a first balanced signal, the first and
second contacts comprise a second contact pair for carrying a
second balanced signal, the third and sixth contacts comprise a
third contact pair for carrying a third balanced signal, the
seventh and eighth contacts comprise a fourth contact pair for
carrying a fourth balanced signal. In these embodiments, at least
one of first, second third and/or fourth contact pairs includes a
crossover. For example, the third contact pair may include a
crossover. Alternatively, the first, second and fourth contact
pairs may each include a crossover. Other crossover arrangements
are also possible.
In some embodiments, the contacts include a contact termination
that is mounted in respective ones of a plurality of metal-plated
holes in the printed circuit board. In these embodiments, the
printed circuit board may include a compensation circuit that is
electrically connected by respective conductive traces to at least
two of the plurality of metal-plated holes. The communications
connector may also include a housing. In some embodiments, the
contact termination is fixedly mounted in the housing.
Pursuant to further embodiments of the present invention,
communications connectors are provided that include a printed
circuit board and a plurality of contacts. The printed circuit
board includes a plurality of signal carrying paths that connect a
plurality of input terminals of the connector to respective of a
plurality of output terminals. Each of the contacts have a mounted
end at which the contact is mounted within the connector, and a
plug contact region that comprises one of the plurality of input
terminals. In these connectors, at least some of the mounted ends
of the contacts comprise branches off of the signal carrying
paths.
The printed circuit board may include a plurality of contact pads,
and each of the contacts may include a pad contact region that is
configured to mate with a respective one of the contact pads. The
pad contact region of each contact may be, for example, (1) between
the mounted end of the contact and the plug contact region of the
contact or (2) between the plug contact region of the contact and a
free end of the contact.
Each contact may be mounted on a first surface of the printed
circuit board and wrap around to extend above a second, opposing
surface of the printed circuit board. The contacts may be
free-floating where they wrap around the edge of the printed
circuit board. Alternatively, the mounted end of each contact may
be fixedly mounted in a housing of the connector. The contacts may
be disposed in a parallel side-by-side relationship over at least
half of the contacts length. Moreover, the free ends of at least
two adjacent ones of the contacts may be staggered with respect to
each other to increase the distance between their free ends.
According to still further embodiments of the present invention,
modular jacks are provided that include a printed circuit board, a
plurality of raised contact pads on a first surface of the printed
circuit board, and a plurality of contacts that are aligned with
respective ones of the raised contact pads. In these jacks, each of
the contacts is configured to make electrical contact with a
respective one of the plurality of raised contact pads at a point
above the first surface of the printed circuit board when the
modular plug is inserted in the modular jack.
In certain embodiments of these jacks, the raised contact pads may
comprise nails that are mounted in respective metal-plated holes on
the printed circuit board. The upper surface of each nail may, in
certain embodiments, have a dome-shape. Each nail may include a
surface that includes gold that directly mates with a respective
one of the first plurality of contacts. The head portion of the
raised contact pad may, in certain embodiments, be at least three
times thicker than the thickness of a plurality a signal carrying
traces that are provided on the printed circuit board. In still
other embodiments, the raised contact pads may comprise small
springs that are mounted in respective metal plated holes on the
printed circuit board.
Pursuant to still further embodiments of the present invention,
communications connectors are provided that include a plurality of
contacts. Each contact has a contact termination that is mounted in
a mounting surface. The contacts further include a printed circuit
board that comprises a structure separate from (but perhaps
connected to) the structure that includes the mounting surface. The
printed circuit board further includes a plurality of contact pads
that mate with respective ones of the contacts, a plurality of
output terminals, and a plurality of conductive paths that
electrically connect at least some of the contact pads to
respective ones of the output terminals.
In some embodiments, the mounting surface may comprise a surface on
a dielectric housing of the communications connector. In other
embodiments, the mounting surface may be a second printed circuit
board.
Pursuant to yet further embodiments of the present invention,
modular jacks are provided that include a printed circuit board
that includes a plurality of contact pads, a plurality of output
terminals, and a plurality of conductive paths that electrically
connect at least some of the contact pads to respective ones of the
output terminals. The jacks further include a plurality of
contacts, each contact having a mounted end, a free end and a
middle portion extending between the mounted end and the free end.
In these jacks, each of the contact pads are mounted to make
electrical contact with the middle portion of respective ones of
the contacts when a plug is in place in the modular jack.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the use of modular plug and modular jack
connectors to interconnect a computer with a communications
cable.
FIG. 2 shows the modular jack contact wiring assignments for an
8-position telecommunications outlet (T568B) as viewed from the
front opening of a jack.
FIG. 3 is an exploded perspective view of a communications
connector according to embodiments of the present invention.
FIG. 4 is a side view of the communications connector of FIG. 3
taken along the line 4-4 of FIG. 3.
FIG. 5 is a side view of one of the jackwire contacts of the
communications connector of FIG. 3.
FIG. 6 is a perspective view of the printed circuit board and
jackwire contacts of the communications connector of FIG. 3 with
four of the jackwire contacts removed to more clearly illustrate
the configuration of the contact pads provided on the printed
circuit board.
FIG. 7 is a plan view of the printed circuit board of FIG. 3 with
exemplary circuit traces shown thereon.
FIG. 8 is an exploded perspective view of a communications
connector according to further embodiments of the present
invention.
FIG. 9 is an exploded perspective view of a communications
connector according to additional embodiments of the present
invention.
FIG. 10 is a cross-sectional view of a printed circuit board with a
nail that may be used as a raised contact pad according to
embodiments of the present invention.
FIG. 11 is a plan view of a portion of the printed circuit of the
communications connector of FIG. 9 illustrating an arrangement in
which the raised contact pads are arranged in multiple rows.
FIG. 12 is an exploded perspective view of a communications
connector according to still further embodiments of the present
invention.
FIG. 13 is an exploded perspective view of a communications
connector according to additional embodiments of the present
invention.
FIG. 14 is a schematic diagram of a communications connector
according to still additional embodiments of the present
invention.
FIG. 15 is a schematic diagram of a communications connector
according to other embodiments of the present invention.
FIG. 16 is a perspective view of the assembly 20 of FIG. 3 in a
partially assembled state.
FIG. 17 is cross-sectional view taken along the line 17-17 in FIG.
16.
FIG. 18 is a perspective view of the assembly 20 of FIG. 3 in a
partially assembled state using an alternative mandrel.
FIG. 19 is cross-sectional view taken along the line 19-19 in FIG.
18.
DETAILED DESCRIPTION
The present invention will be described more particularly
hereinafter with reference to the accompanying drawings. The
invention is not intended to be limited to the illustrated
embodiments; rather, these embodiments are intended to fully and
completely disclose the invention to those skilled in this art. In
the drawings, like numbers refer to like elements throughout.
Thicknesses and dimensions of some components may be exaggerated
for clarity.
Spatially relative terms, such as "under", "below", "lower",
"over", "upper", "top", "bottom" and the like, may be used herein
for ease of description to describe one element or feature's
relationship to another element(s) or feature(s) as illustrated in
the figures. It will be understood that the spatially relative
terms are intended to encompass different orientations of the
device in use or operation in addition to the orientation depicted
in the figures. For example, if the device in the figures is turned
over, elements described as "under" or "beneath" other elements or
features would then be oriented "over" the other elements or
features. Thus, the exemplary term "under" can encompass both an
orientation of over and under. The device may be otherwise oriented
(rotated 90 degrees or at other orientations) and the spatially
relative descriptors used herein interpreted accordingly.
Well-known functions or constructions may not be described in
detail for brevity and/or clarity.
As used herein the expression "and/or" includes any and all
combinations of one or more of the associated listed items.
The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises", "comprising", "includes" and/or
"including" when used in this specification, specify the presence
of stated features, integers, steps, operations, elements, and/or
components, but do not preclude the presence or addition of one or
more other features, integers, steps, operations, elements,
components, and/or groups thereof.
Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention belongs. It will be further understood that terms, such
as those defined in commonly used dictionaries, should be
interpreted as having a meaning that is consistent with their
meaning in the context of the relevant art and will not be
interpreted in an idealized or overly formal sense unless expressly
so defined herein.
This invention is directed to communications connectors, with a
primary example of such being a communications jack. As used
herein, the terms "forward", "forwardly", and "front" and
derivatives thereof refer to the direction defined by a vector
extending from the center of the jack toward the plug opening of
the jack. Conversely, the terms "rearward", "rearwardly", and
derivatives thereof refer to the direction directly opposite the
forward direction; the rearward direction is defined by a vector
that extends away from the plug opening toward the remainder of the
jack. Where used, the terms "attached", "connected",
"interconnected", "contacting", "mounted" and the like can mean
either direct or indirect attachment or contact between elements,
unless stated otherwise.
FIG. 3 is an exploded perspective view of a communications
connector 10 according to embodiments of the present invention.
FIG. 4 is a side view of the communications connector 10 taken
along the line 4-4 of FIG. 3. FIG. 5 is a side view of one of the
jackwire contacts 50 of the electrical connector 10 that
illustrates various portions of a representative jackwire contact
50. FIG. 6 is a perspective view of the printed circuit board 30
and jackwire contacts 50 of the communications connector 10 with
four of the jackwire contacts removed. FIG. 7 is a plan view of the
printed circuit board 30. In FIG. 7, the conductive traces are
shown as existing on the top layer/surface of printed circuit board
30 for ease of description, but it will be appreciated that all or
parts of one or more of the traces would be implemented on
additional layers of the printed circuit board 130. The
communications connector 10 of FIGS. 3-7 comprises a modular jack
that is configured to mate with a modular plug (not shown in FIGS.
3-7).
As shown in FIG. 3, the communications connector 10 comprises an
assembly 20, which is enclosed within an electrically insulative or
dielectric jack housing 12, terminal housing 14 and cover 16. The
jack housing 12 receives a front part of the assembly 20 which is
inserted into an opening in the rear of the jack housing 12. The
jack housing 12 further includes an opening 13 that is sized and
configured to receive a modular plug (not shown in FIG. 3) that is
inserted into the jack housing 12 along the axis P. Terminal
housing 14 is fitted over and protects an upper surface of the
assembly 20. Cover 16 fits beneath the assembly 20 and attaches to
the terminal housing 14 to protect a lower surface of the assembly
20.
The assembly 20 includes a printed circuit board 30. The printed
circuit board 30 may comprise, for example, a single or
multi-layered dielectric substrate that includes a top surface 32,
a bottom surface 34, a forward edge 36 and a rear edge 38. The
printed circuit board 30 further includes a plurality of conductive
traces or paths 48 (see FIG. 7) that extend between input terminals
40 of the printed circuit board 30 and output terminals 42. In the
particular embodiment pictured in FIGS. 3-7, the input terminals 40
of the printed circuit board 30 are located at or adjacent to the
forward edge 36 of the printed circuit board 30, and the output
terminals 42 are located in two rows that extend from approximately
the middle of the printed circuit board 30 to the rear edge 38 of
the board 30. It will be understood that the printed circuit board
30 may comprise any conventional printed circuit or wiring board, a
flexible printed circuit board, or any other type of substrate that
includes conductive paths that connect input terminals to
respective output terminals. As discussed in more detail herein,
the printed circuit board 30 may also include electrical circuit
components or devices arranged on or within the board to compensate
for crosstalk that may otherwise be present in the connector. Such
devices include, but are not limited to, closely spaced wire traces
printed on or within layers of the printed circuit board 30, plate
capacitors implemented on two or more layers or surfaces of the
board, interdigitated finger capacitors such as the capacitors
disclosed, for example, in U.S. Pat. No. 5,997,358, and discrete
electrical components such as inductors, capacitors or resistors
that are mounted on or within the printed circuit board 30. While
specific layouts for such compensation circuits are not set forth
in detail herein, the aforementioned '358 patent, for example,
describes methods for designing such compensation circuits.
Turning again to FIG. 3, in addition to the printed circuit board
30, the assembly 20 further includes a number (in this particular
embodiment, eight) of spring jackwire contacts 50 that wrap around
the forward edge 36 of the printed circuit board 30. Herein, the
term "contact", when used as a noun, refers to an electrically
conductive element that is designed to establish physical and
electrical contact with an external electrically conductive
element. The jackwire contacts 50 depicted in FIG. 3 are one such
type of contact that is known in the art. The jackwire contacts 50
extend above the printed circuit board 30 at an acute angle
relative to the top surface 32 of the printed circuit board 30. The
assembly 20 also includes a plurality of wire connection terminals
70 that are mounted in the output terminals 42 of the printed
circuit board (in the embodiment of FIG. 3, the output terminals
comprise the metal-plated holes 44 that receive the wire connection
terminals 70). In the embodiment of FIG. 3, the wire connection
terminals 70 are implemented as insulation displacement terminals
(IDCs). The IDCs 70 may also include a base having a "needle-eye"
construction that allows the base to be pushed into the
metal-plated holes 44. The metal-plated holes 44 may have a
diameter that is slightly less than the diameter of the needle-eye,
which may facilitate providing a reliable electrical connection
between each DC 70 and its respective metal-plated hole 44 without
a need for soldering. The IDCs or other wire connection terminals
70 may alternatively be soldered in place or press-fit in place by
other means. It will also be appreciated that the wire connection
terminals 70 may be replaced with other forms of output terminals
such as, for example, jackwire contacts.
The terminal housing 14 mounts over the wire connection terminals
70 to further hold the DC terminals 70 in place and/or to protect
the IDC terminals 70 and the top surface 32 of the printed circuit
board 30. The terminal housing 14 also permits wire lead access to
the DC terminals 70. The terminal housing 14 includes a pair of
mounting posts 18 that project from a bottom surface of the
terminal housing 14. When the terminal housing 14 is aligned with
the IDC terminals 70 on the printed circuit board 30 and lowered to
surround the IDC terminals 70, the mounting posts 18 align with a
pair of mounting holes 49 provided in the printed circuit board 30
and pass through them to project from the bottom surface 34 of the
printed circuit board 30.
The cover 16 may protect the bottom surface 34 of at least part of
the printed circuit board 30. The cover 16 includes a pair of
openings (not shown in FIG. 3) that are formed along a center line
between sides of the cover 16 that align with tips of the terminal
housing mounting posts 18. The printed circuit board 30 is
"sandwiched" or captured between the terminal housing 14 and the
cover 16, and the tips of the mounting posts 18 may be joined to
the body of the cover 16 by, for example, an ultrasonic welding
probe inserted into the cover openings from below the cover 16. The
tips of the mounting posts 18 and the surrounding body of the cover
16 melt and fuse with one another to form solid joints when cooled.
With the printed circuit board 30 thus captured between the
terminal housing 14 and the cover 16, most or all of the rear
portion of the printed circuit board 30 may be protectively
enclosed.
As also shown in FIG. 3, the jack housing 12 has a latch 15
protruding below its rear opening. The bottom forward edge of the
cover 16 includes a raised protrusion that mates with the latch 15.
The terminal housing 14 likewise has a pair of side catches 22
protruding from the forward part of both sides of the housing. The
side catches 22 may comprise, for example, snap clips that have
hooked projecting ends that are configured to snap into and lock
within respective recesses 24 provided in the side walls of the
jack housing 12. Once the terminal housing 14 is joined to the
cover 16 with the circuit board 30 captured between them, the
forward edge 36 of the printed circuit board 30 is inserted into
the rear opening in the jack frame 12 until the side catches 22
snap into place in their respective recesses 24 in the jack housing
and until the latch 15 snaps over and onto the raised protrusion on
the bottom of cover 16 to securely join the jack housing 12 to the
remainder of the connector 10.
The jack housing 12, the terminal housing 14 and the cover 16 may
be formed, for example, of a plastics material that meets
applicable standards with respect to electrical insulation and
flammability, such as Polyvinyl Chloride (PVC), Acrylonitrile
Butadiene Styrene (ABS), or polycarbonate. It will be appreciated
that many other electrically insulative or dielectric materials may
be used.
While the jack housing 12, the terminal housing 14 and the cover 16
provide one example of a housing structure that may enclose the
assembly 20, it will be appreciated that a wide variety of
different housing structures could be used, and/or that the
assembly 20 could be constructed as part of the housing itself as
opposed to a separate piece. Thus, embodiments of the present
invention need not be limited to any particular housing structure,
and the above-provided detailed description of one particular
housing arrangement is provided so that the present disclosure will
be thorough and complete.
As shown best in FIGS. 4-5, each jackwire contact 50 may include a
mounted end 52 (also referred to herein as a "contact
termination"), a lower section 53, a vertical section 54, a pad
contact region 56, a plug contact region 58 and a free end 59. The
jackwire contacts 50 may be formed, for example, of a copper alloy
such as spring-tempered phosphor bronze, beryllium copper, or the
like. A typical cross-section of each jackwire contact 50 is 0.015
inch wide by 0.010 inch thick, although other sized contacts may be
used.
The mounted end 52 of each jackwire contact 50 is mounted in
respective ones of a plurality of metal-plated openings 44 that are
provided on the bottom surface 34 of the printed circuit board 30
(note that the metal-plated openings 44 may extend all the way up
to the top surface 32 of the printed circuit board 30). The
"mounted end" 52 of a contact refers to an end portion of the
contact that is securely mounted (i.e. held in a fixed position) in
some structure such as, for example, a printed circuit board or a
portion of the jack housing. The mounted ends 52 of the jackwire
contacts 50 may have a "needle eye" construction that allows the
ends to be pushed into the metal-plated holes 44. The metal-plated
holes 44 may have a diameter that is slightly less than the
diameter of the mounted ends 52 of the jackwire contacts 50, which
may facilitate providing a reliable electrical connection between
each jackwire contact 50 and its respective metal-plated hole 44
without a need for soldering.
The lower section 53 of each jackwire contact 50 runs generally
parallel to and beneath the bottom surface 34 of the printed
circuit board 30. The vertical section 54 of each contact runs
adjacent to the forward edge 36 of the printed circuit board 30. As
shown best in FIG. 4, in the embodiment of FIGS. 3-7, the vertical
sections 54 of the jackwire contacts 50 may be "free-floating" in
that they do not contact the forward edge 36 of the printed wiring
board 30 when a plug is not inserted in the jack housing 12. This
allows the jackwire contacts to deflect from the curved portion
between the lower section 53 and the vertical section 54.
The plug contact region 58 refers to the portion of a jackwire
contact 50 that makes mechanical and/or electrical contact with the
contacts and/or housing of a modular plug that is inserted into the
communications connector 10. The pad contact region 56, as
discussed below, is the portion of a jackwire contact 50 that makes
physical and electrical contact with a corresponding contact pad 46
(see FIG. 6) that is provided on the printed wire board 30. In
certain embodiments of the present invention, the pad contact
region 56 and the plug contact region 58 may be overlapping or
co-located.
As shown in FIG. 3, the jackwire contacts 50 are arranged in a
parallel side-by-side relationship throughout substantially their
entire length. In particular, the eight contacts 50 are arranged in
a row, and each jackwire contact 50 maintains a substantially
constant distance from its one or two neighboring jackwire contacts
50 over substantially the entire length of the contacts. The
jackwire contacts 50 according to certain embodiments of the
present invention may be relatively simple to manufacture and
install within the connector.
In operation, a modular plug (not shown in FIGS. 3-7) is inserted
along the axis P into the opening 13 included in the front face of
jack housing 12. When the modular plug is inserted into the opening
13, blades or other contacts of the plug contact respective ones of
the jackwire contacts 50. The jackwire contacts 50 may comprise
spring jackwires that are resiliently deflected by the plug blades
toward the top surface 32 of the printed circuit board 30. The
spring force of the deflected jackwires 50 holds the jackwire
contacts 50 in firm contact against respective ones of the plug
blades, thereby establishing an electrical connection between each
of the plug blades and a respective one of the jackwire contacts
50.
Pursuant to embodiments of the present invention, the input
terminals 40 may comprise a plurality of contact pads 46 that are
provided on the printed circuit board 30. Each of the contact pads
46 is arranged so as to mate with the pad contact region 56 of a
respective one of the jackwire contacts 50 when a modular plug is
inserted into the modular jack, thereby deflecting the jackwire
contacts 50. The contact pads 46 may be implemented as any
conductive pad or other structure that makes reliable electrical
contact with its respective jackwire contact under appropriate
conditions (e.g., when a plug is inserted into the jack). As
discussed herein, structures having a significant three-dimensional
aspect such as nails, blocks columns or the like may be used as
contact pads 46 in certain embodiments of the present
invention.
FIG. 6 more clearly illustrates one implementation of the contact
pads 46 according to embodiments of the present invention. In FIG.
6, four of the jackwire contacts 50 have been removed to more
clearly show the contact pads 46. As shown in FIG. 6, a plurality
of contact pads 46 are provided along the forward edge 36 of the
printed circuit board 30. The contact pads 46 may also extend onto
the top surface 32 of the printed circuit board 30. In the
embodiment of FIGS. 3-7, a total of eight contact pads 46 are
provided. Each contact pad 46 is positioned to mate with a
respective one of the jackwire contacts 50 when, as discussed
above, a modular plug is inserted into the opening 13 in the jack
housing 12. When the jackwire contacts 50 mate with respective ones
of the contact pads 46, an electrical connection is established
such that an electrical signal may pass from the blade of the
modular plug, to the jackwire contact 50 with which the plug blade
mates, and then through the contact pad 46 that mates with the
jackwire contact 50 at issue. The contact pads 46 may be formed of
a variety of conductive materials such as, for example, copper or
copper alloys (with or without plating). In certain embodiments of
the present invention, the contact pads may comprise a gold or
nickel plated copper alloy.
In the embodiment of FIGS. 3-7, the contact pads 46 are deposited
on the forward edge 36 and a small portion of the top surface 32 of
the printed circuit board 30. It will be appreciated that the
contact pads 46 need not, for example, extend vertically along the
entire forward edge 36 of the printed circuit board 30, as, in the
embodiment of FIGS. 3-7, the electrical connection between each
jackwire contact 50 and its respective contact pad 46 may primarily
occur at the forward edge of the upper surface 32 of the printed
circuit board 30. It will also be appreciated that the contact pads
46 may be located at a wide variety of different places on the
printed circuit board 30. By way of example, FIG. 8 depicts another
embodiment of the present invention in which the contact pads 46
are located exclusively on the top surface 32 of the printed
circuit board 30. In the embodiment of FIGS. 3-7, the vertical
portion of each contact pad 46 is simply plated on the forward edge
36 of the printed circuit board 30. An optional mandrel 41 may be
provided to facilitate keeping the contacts 50 in proper alignment.
In other embodiments, eight grooves may be cut into the forward
edge 36 of the printed circuit board 30, and the conductive plating
that forms the vertical portion of each contact pad 46 is plated on
the side and back walls of each groove. The grooves may be
relatively shallow, but in still other embodiments, the grooves may
be deeper such that the sidewalls of the grooves form a comb
structure that can be used to maintain the individual jackwires in
proper alignment for mating with the modular plug and their
respective contact pads 46, which may eliminate any need for a
mandrel 41. Moreover, in the embodiments that include grooves, the
back wall of each groove may be slanted such that the upper portion
of the groove is wider than the lower portion of the groove. This
slanting may be used to increase the surface area over which the
pad contact region 56 of each jackwire contact 50 makes physical
contact with its corresponding contact pad 46 when a plug is
inserted into the connector 10.
As best shown in FIGS. 4-5, in the communications connector 10 of
FIGS. 3-6, the jackwire contacts 50 are not in contact with their
respective contact pads 46 except when a modular plug is inserted
into the communications connector 10. When a plug is inserted into
the connector 10, the jackwire contact 50 tends to move across the
contact pad 46 as it flexes into its final position, creating a
"wiping action" that may help remove debris from the jackwire
contact 50 and/or contact pad 46 that may interfere with the
electrical connection, and which may also generally result in an
improved electrical connection between the jackwire contact 50 and
the contact pad 46.
As noted above, a mandrel 41 may be provided that facilitates
keeping the contacts 50 in proper alignment. FIGS. 16 and 17 show
the assembly 20 of FIG. 3 in a partially assembled state in order
to better illustrate the mandrel 41. As shown in FIGS. 16 and 17,
the mandrel 41 includes a plurality of recesses 43 that define a
comb structure that acts to properly align the jackwire contacts
50. Jackwire contacts 50 are positioned in respective ones of the
recesses 43 once the assembly 20 is fully assembled (in FIGS. 16
and 17, only a single jackwire contact 50 has been mounted on the
assembly 20). As shown best in FIG. 17, a cross-section taken
through one of the recesses 43 may generally have a flattened
"half-moon" profile adjacent the forward edge 36 of the printed
circuit board 30.
As shown in FIGS. 18 and 19, in other embodiments of the present
invention, a mandrel 41' may be used. In mandrel 41', the top
portion of the mandrel is removed in each of the recesses 43 such
that a cross-section of the mandrel 41' taken through the recess
has, for example, a flattened "quarter-moon" profile adjacent the
forward edge 36 of the printed circuit board 30. By removing the
upper portion of the mandrel 41' in each of the recesses 43, an
open area 45 is provided in each recess 43 adjacent the top portion
of the forward edge 36 of the printed circuit board 30. Because of
this open area 45, the jackwire contacts 50 will tend to deflect
about a moment arm located at the designation "A" in FIG. 19. The
net result is that there may be increased wiping action between the
jackwire contacts 50 and the contact pads 46, which may act to
clean the jackwire contacts 50 and the contact pad 46 and thereby
provide an improved connection with a lower contact resistance.
As can also be seen from FIGS. 4-5, when a plug is inserted into
the communications connector 10, the bend between the lower segment
53 and the vertical segment 54 of each jackwire will tend to act as
a fulcrum, such that at least the vertical segment 54, the pad
contact region 56, the plug contact region 58 and the free end 59
will move when the plug is inserted. Thus, together each of the
above regions of each jackwire contact 50 comprises part of a
mobile region of the jackwire contact 50. By allowing the jackwire
contacts 50 to flex along a substantial length below the plug
contact region 58 it is possible to shorten the free ends 59 of the
jackwire contacts 50, which may facilitate reducing the amount of
crosstalk generated in the free ends of the jackwire contacts
59.
While the "free-floating" configuration of the jackwire contacts 50
may be desirable in some applications, when the contacts 50 spring
away from the contact pads 46 as a modular plug is removed from the
communications connector 10, a generally undesirable current arcing
phenomena may occur between the jackwire contacts 50 and the
contact pads 46. Accordingly, according to further embodiments of
the present invention, the jackwire contacts 50 may be arranged so
that they make electrical contact with their respective contact
pads 46 regardless of whether or not a modular plug is mated with
the communications connector 10.
As shown best in FIG. 7, a plurality of conductive paths 48 are
provided on the printed circuit board 30 that extend between the
input terminals 40 of the printed circuit board 30 and the output
terminals 42 of the printed circuit board 30. As noted above, in
FIG. 7, the conductive traces have all been shown as existing on
the top surface of printed circuit board 30 for ease of
description. However, it will be appreciated that all or parts of
one or more of the traces would be implemented on additional layers
of the printed circuit board 30 to facilitate crossing conductive
paths 48 without creating a short-circuit between paths and/or to
implement compensation stages (not shown in FIG. 7) on the printed
circuit board 30.
In the embodiment of FIGS. 3-7, the contact pads 46 comprise the
input terminals 40 through which communications signals are coupled
onto the printed circuit board, and the metal-plated holes 44 that
receive the IDCs 70 comprise the output terminals 42. Herein,
"input terminals" and "output terminals" refer to, respectively,
the structure through which electrical signals are transferred into
or out of something (e.g., a printed circuit board, a
communications connector, etc.). It will be understood that whether
or not a particular structure comprises an "input" terminal or an
"output" terminal will depend upon the direction of travel of the
electrical signal. To simplify the description, a like set of
terminals (e.g., the jackwire contacts or the IDCs) are referred to
collectively as either a set of "input" terminals or a set of
"output" terminals, even though in operation some of the electrical
signals may travel in different directions.
As noted above, in the communications connector 10, each of the
conductive paths 48 connects one of the contact pads 46 to a
respective one of the insulation displacement connectors 70. The
conductive paths 48 may be dimensioned and arranged on one or more
layers of the printed circuit board 30 in such a manner that
crosstalk is substantially reduced over an entire connection
comprising the electrical connector 10 and an associated plug. U.S.
Pat. No. 5,997,358, incorporated by reference herein, depicts a
connector having a printed circuit board with eight layers that
implements a multi-stage compensation scheme for substantially
eliminating crosstalk that is present at the input terminals of the
printed circuit board. Such crosstalk compensation schemes may be
implemented in numerous different forms, and may rely on, for
example, inductive and or capacitive coupling between the
conductive paths 48 and/or discrete components such as resistors,
capacitors and inductors for crosstalk reduction between pairs of
conductive paths. Embodiments of the present invention are not
limited to any particular type or strategy for reducing and/or
eliminating crosstalk on the printed circuit boards of the
connectors disclosed herein, and it will also be appreciated that
at least some of the crosstalk compensation may be achieved in
other locations such as in the jackwire contacts (which are also
referred to sometimes herein as "the leadframe"), in the plug, in a
second printed circuit board, etc.
In the embodiment of FIGS. 3-7, each of the conductive traces 48
comprises part of a signal carrying path that extends from one of
the input terminals 40 to a respective one of the output terminals
42 of the communications connector 10. This signal carrying path,
thus, carries a signal that is input from a plug contact onto one
of the jackwire contacts 50 of the connector 10 to a corresponding
IDC 70. Herein, the term "signal carrying path" refers to a direct
path that may be used to carry a signal coupled onto an input
terminal of the connector to an output terminal of the connector.
It will be appreciated that, in many cases, branch segments will
extend from one or more of the signal carrying paths within a
communications connector. These branch segments may be electrically
connected to the signal carrying path, but are not part of the
signal carrying path, as the branch segments "dead-end" and hence
the input signal generally does not traverse the branch when
traveling from the input terminal to the output terminal of the
connector. By way of example, in the communications connector 10 of
FIGS. 3-7, eight signal carrying paths are provided, each of which
extends from the plug contact region 58 of one of the jackwire
contacts 50, along the jackwire contact 50 to the pad contact
region 56, through the corresponding contact pad 46, along the
conductive trace 48 that is coupled to the contact pad 46, through
one of the metal-plated IDC holes 44 to which the other end of the
conductive trace 48 connects, and finally through one of the IDCs
70. Various branch segments extend from each of these signal
carrying paths, such as, for example, the free end 59 of each
contact and the vertical and lower segments 53, 54 of each contact.
These branches are electrically connected to the signal carrying
path, but are not part of the signal carrying path, as they
"dead-end" instead of providing a conductive path from the input of
the connector to the output of the connector. Various other
branches that are not part of the signal carrying path may also be
provided such as, for example, interdigitated and/or plate
capacitors that may be connected to the metal-plated hole 44 that
receives the termination end 52 of the jackwire contact and/or
which branch directly off of the contact pads 46, the conductive
paths 48 and/or the metal-plated holes 44 that receive the IDCs 70.
It will also be appreciated that more than one signal carrying path
may exist between a specific input terminal and its respective
output terminal. In such cases, both paths together constitute the
signal carrying path.
The jackwire contacts 50 of communications connector 10 run
parallel to each other along substantially their entire length.
These jackwire contacts 50 may be simpler and less expensive to
manufacture than the jackwires contacts included in many
conventional communications connectors that include, for example,
crossing contacts. Moreover, the contact pads 46 may be located at
a relatively short electrical distance from the plug contact area
58 of the contacts, thereby providing a leadframe structure that
has a relatively short delay. As a result, the additional crosstalk
generated in the leadframe may be relatively small, and may be
relatively easy to compensate for on, for example, the printed
circuit board 30.
FIG. 8 is a perspective view of an assembly 120 for a connector
according to embodiments of the present invention. The assembly 120
could be used in conjunction with, for example, the same housing
structures included with the connector 10 of FIGS. 3-7.
As shown in FIG. 8, the assembly 120 includes a printed circuit
board 130, a plurality of jackwire contacts 150 having mounted ends
that are mounted in the bottom surface 134 of the printed circuit
board 130, and a plurality of DC terminals 170. The printed circuit
board 130 includes a plurality of conductive paths 148 (not shown
in FIG. 8), and a plurality of contact pads 146 are mounted on the
top surface 132 of the printed circuit board 130 at or adjacent the
forward edge 136 of the circuit board 130.
In the embodiment of FIG. 8, the contact pads 146 are only provided
on the top surface 132 of the printed circuit board 130. In
particular, the contact pads 146 do not extend around the forward
edge 136 of the printed circuit board 130 as do the contact pads 46
depicted in the embodiment of FIGS. 3-7. By forming the contact
pads 146 on only a single surface of the printed circuit board 130,
it may be possible to simplify the manufacture of the printed
circuit board, which may result in cost savings.
In order to provide a more robust and reliable mechanical and
electrical connection between the jackwire contacts 150 and their
respective contact pads 146 in the embodiment of FIG. 8, the
jackwire contacts 150 may include one or more undulations 151 such
as the U-shaped bend shown in each of the jackwire contacts 150.
Herein, references to an "undulation" in a contact refer to a
portion of the contact that dips closer to a printed circuit board
to make electrical contact a contact pad when a plug is inserted
into the connector. The undulation may, for example be U-shaped or
V-Shaped, and it may be shallow or deep. The undulation also need
not be symmetric.
As shown in FIG. 8, the undulation 151 in each jackwire contact 150
is positioned directly over the corresponding contact pad 146. When
a modular plug is brought into contact with the jackwire contacts
150 (i.e., when the modular plug is inserted into a communications
connector that includes the assembly 120), the jackwire contacts
150 are forced downward to mate with their respective contact pads
146, and the undulation 151 in each contact makes mechanical and
electrical connection with its corresponding contact pad 146.
Typically, a wiping action will result where the undulation region
151 of the jackwire contact 150 wipes across the contact pad 146 to
provide a robust electrical connection.
Note that in the embodiment of FIG. 8, the pad contact region 156
of each jackwire contact 150 may be moved closer to the plug
contact area 158 of each contact. As a result, the electrical
distance between the plug contact area 158 and the contact pads 146
may be reduced.
FIG. 9 is a perspective view of a connector 210 that includes an
assembly 220 according to further embodiments of the present
invention. To simplify the description, the connector 210 is
illustrated as including the same housing structures as the
connector 10 of FIGS. 3-7. Consequently, the housing structures are
not numbered in FIG. 9, and the description below is limited to the
assembly 220 which contains certain differences from the assembly
20 of the connector 10 described above.
As shown in FIG. 9, the assembly 220 includes a plurality of raised
contact pads 246. The contact pads 246 are referred to as "raised"
contact pads because they extend above the upper surface of the
printed circuit board 230 (it will be understood that herein the
"upper surface" of the printed circuit board is defined by the
higher of the upper portion of the dielectric board and the upper
portion of any conductive traces that are provided on the
dielectric board). By using raised contact pads 246, the electrical
distance between the plug contact region 258 of each jackwire
contact 250 and its corresponding contact pad 246 can be reduced as
compared to, for example, the corresponding distance between the
plug contact region 58 of each jackwire contact 50 and its
corresponding contact pad 46 in the communications connector 10 of
FIGS. 3-7. As noted above, by reducing this electrical distance, it
may be possible to reduce the additional crosstalk introduced in
the leadframe, which may improve the overall crosstalk performance
of the connector.
In embodiments of the present invention, the raised contact pads
246 may be implemented, for example, as small nails that are
inserted into plated-metal holes 244 in the printed circuit board
230. Such nails may be purchased commercially. For example,
Mill-Max (www.mill-max.com) offers a "printed circuit pin" product
which comprises a small nail that may be used in certain
embodiments of the present invention. It will be appreciated that
herein, the term "nail" is intended to refer to any object that
includes a base portion that may be inserted into a substrate (or
into a hole in a substrate) and a head portion that is connected to
the base portion and that extends above the substrate when the nail
is in place, and thus the term "nail" is not limited to just
traditional "nails." The nails may comprise, for example, brass
nails that are plated with gold or another highly conductive metal.
Alternatively, the nails may be made from pure gold, although the
use of such nails may increase the overall cost of the connector.
The gold or other plating may be thicker on the raised or "head
portion" of the nail that makes physical contact with a
corresponding jackwire contact 250. By providing thicker plating on
the head portion of the nail the possibility of the plating wearing
away with use may be reduced, while minimizing the total amount of
gold used to form the raised contact pad 246.
In further embodiments of the present invention, the raised contact
pads may comprise small spring contact pads that are mounted in the
printed circuit board. By way of example, small printed circuit
board spring contact pads are available commercially from Cinch
(the Cinch "iQ" contacts). The use of such spring contact pads may
provide for more robust and reliable electrical connections between
the jackwire contacts and the contact pads.
In certain embodiments of the present invention, the top surface
247 of the nail or other raised contact pad 246 may have a
dome-shaped surface as shown, for example, in FIG. 10. The use of
such a domed surface may increase the surface area over which the
jackwire contact 250 and the raised contact pad 246 physically
contact during operation of the connector. Herein, the term
"dome-shaped surface" is intended to include hemispherical shapes,
partial ovoid shapes and any other generally or partially rounded
three dimensional shapes that are designed to increase the surface
area over which the jackwire contact 250 and the raised contact pad
246 physically contact during operation. It will also be
appreciated that the top surface may have other shapes such as a
sloped or pyramidal shape that can be used to increase the surface
area over which contact is made.
The raised contact pads 246 pictured in FIGS. 9-10 above may be
more physically robust than the contact pads 46 or 146 in the
embodiments of FIGS. 3-7 and FIG. 8, respectively, as the raised
contact pad 246 may include a thicker metal top surface 247 that is
less prone to wearing away. For example, in certain embodiments,
the head portions of the raised contact pads 246 may be 10-30 mils
thick or more. The use of raised contact pads 246 also facilitates
positioning the contact pads away from the forward edge of the
circuit board 230 without necessarily requiring an additional bend
in the jackwire contacts such as the undulation 151 provided in the
jackwire contacts 150 of FIG. 8.
As shown in FIG. 11, the raised contact pads 246 may be arranged in
two or more rows. The use of multiple rows of raised contact pads
may help reduce the possibility of arcing or short circuits between
adjacent raised contact pads 246, and may also provide increased
room for running conductive traces to each of the raised contact
pads 246 in or on the printed circuit board 230. In certain
embodiments of the present invention, the distance "d" shown in
FIG. 11 between the first and second rows of raised contact pads
may be between, for example, about 40-60 mils. When such a
multi-row configuration of raised contact pads is employed, the
contact pads in the second row may be taller than the contact pads
in the first row. By having raised contact pads 246 with such
different heights, it may be possible to have the jackwire contacts
250 exert approximately the same amount of force on each raised
contact pad 246 regardless of whether or not the raised contact pad
is in the first or second row. It will also be appreciated that the
contact pattern depicted in FIG. 11 is exemplary, and that numerous
other patterns could be employed.
Pursuant to further embodiments of the present invention,
communications connectors are provided that include jackwire
contacts that have crossovers or other configurations that are
designed to introduce crosstalk compensation within the lead frame.
FIG. 12 is an exploded perspective view of a communications
connector 310 that includes jackwire contacts 350a-350h which cross
over one another in order to introduce compensating crosstalk in
the leadframe of the connector. In particular, jackwire contacts
350a and 350b cross over each other to trade positions within the
lead frame, as do jackwire contacts 350d and 350e and 350g and
350h. As the communications connector 310 is identical to the
communications connector 10 except for the crossovers in the
leadframe, further discussion of the connector 310 will be
omitted.
In another embodiment not pictured herein, jackwire contacts 350c
and 350f cross over each other to trade positions in the leadframe
in place of the crossovers of jackwire contacts 350a/350b,
350d/350e and 350g/350h depicted in FIG. 12. Moreover, in the
embodiment of FIG. 12, the crossovers are located adjacent the
forward edge of the printed circuit board 330. It will also be
appreciated that, according to further embodiments of the present
invention, the crossovers may be located in a variety of different
locations such as, for example, adjacent the free ends of the
jackwire contacts, between the plug contact region and the pad
contact region of the contacts and/or in the lower segment.
Pursuant to further embodiments of the present invention, the
jackwire contacts may be configured to introduce compensating
crosstalk in the leadframe without the use of crossovers. By way of
example, as shown in FIG. 13, a communications connector 410 may be
provided that is almost identical to the communications connector
10 of FIGS. 3-7, except that the free ends 459 of the jackwire
contacts 450 of communications connector 410 are "staggered" beyond
(and possibly in) the plug contact region 458 so that the distance
between at least some of the adjacent jackwire contacts 450 is
increased. For example, as shown in FIG. 13, the free ends 459 of
the jackwire contacts 450c and 450e are bent downwardly, while the
free ends 459 of the jackwire contacts 450d and 450f are bent
upwardly. In this manner, the amount of offending crosstalk
generated, for example, between contacts 450c and 450d and between
contacts 450e and 450f may be reduced and, depending upon the
relative configuration of the free ends 459 of contacts 450c-450f,
compensating crosstalk may even be introduced. The stagger may be
included in the free ends of additional and/or different contacts,
and numerous different staggering techniques may be used.
FIG. 14 is an exploded perspective view of a communications
connector 510 according to yet another embodiment of the present
invention. The communications connector 510 is similar to the
communications connector 10 discussed above. However, in the
communications connector 510, the mounted ends 552 of the jackwire
contacts 550 are mounted into the top surface 532 of the printed
circuit board 530, and thus the jackwire contacts 550 do not wrap
around the printed circuit board 530 as do the jackwire contacts 50
in the communications connector 10. A plurality of contact pads 546
are provided adjacent the forward edge 536 of the top surface 532
of the printed circuit board 530. The free end of each contact is
configured to mate with a respective one of the contact pads 546
when a modular plug is inserted into the connector 510. A plurality
of traces are provided on one or more layers of the printed circuit
board 530 that connect each of the contact pads 546 to a respective
one of the IDCs 570. Crosstalk compensation circuits may be
provided on the printed circuit board 530 that are connected to the
contact terminations 552 of one or more of the jackwire contacts
550. U.S. Pat. No. 6,350,158, which is incorporated by reference
herein as if set forth in its entirety, provides further details
regarding particular configurations for jackwire contacts and
contact pads that may be employed in the embodiment of FIG. 14.
The connector 510 depicted in FIG. 14 also has a leadframe that
includes three crossovers at which one jackwire contact 550 of a
pair is stepped toward and crosses over the other jackwire contact
of the pair, with a generally "S"-shaped side-wise step. Each
crossover may be implemented by having the jackwire contacts of a
wire pair curve arcuately above and below their common plane at
each cross-over location. Opposing faces of the jackwire contacts
may, for example, be spaced by about 0.040 inches (i.e., enough to
prevent shorting when the jackwire contacts 550 are engaged by a
modular plug).
FIG. 15 is a schematic diagram of portions of a communications
connector 610 according to still further embodiments of the present
invention. As shown in FIG. 15, the connector 610 includes a
printed circuit board 630 and a plurality of jackwire contacts 650
(only one jackwire contact is pictured in FIG. 15). The mounted
ends 652 of the jackwire contacts 650 are mounted in a first
substrate 680. This first substrate 680 may comprise, for example,
part of a dielectric jack housing or some other portion of the body
of the connector 610. The substrate 680 could also comprise a
second printed circuit board. The printed circuit board 630
includes a plurality of contact pads 646 that are configured to
mate with free end portions 659 of respective of the jackwire
contacts 650.
When a modular plug (an exemplary blade is depicted in FIG. 15) is
inserted into the connector 610, the free ends 659 of the jackwire
contacts are in electrical and mechanical contact with respective
of the contact pads 646. A plurality of conductive traces (not
shown in FIG. 15) are provided on the printed circuit board 630
that connect each of the contact pads 646 to respective output
terminals of the connector (which are not depicted in FIG. 15). The
printed circuit board 630 may farther include crosstalk
compensation elements (not shown in FIG. 15) that may be
electrically connected to, for example, the conductive traces 648.
Crosstalk compensation circuits may also be mounted in the
substrate 680 and connected to one or more of the mounted ends 652
of the jackwire contacts 650.
In the embodiment of FIG. 15, the mounted ends 652 of the jackwire
contacts 650 are mounted in a first substrate (substrate 680),
while the plurality of conductive traces that carry the respective
signals to the output terminals of the connector are mounted in or
on a second substrate (namely printed circuit board 630). Such an
embodiment may be particularly well suited for patch panel
applications, where typically the printed circuit board is mounted
at an angle normal to the axis on which a plug enters the
connector. Patch panels are known to those of skill in the art and
include, for example, panels that include one or more rows of
connector modules, where each connector module includes a plurality
of modular jacks and/or rows of modular jacks.
The foregoing is illustrative of the present invention and is not
to be construed as limiting thereof. Although exemplary embodiments
of this invention have been described, those skilled in the art
will readily appreciate that many modifications are possible in the
exemplary embodiments without materially departing from the novel
teachings and advantages of this invention. Accordingly, all such
modifications are intended to be included within the scope of this
invention as defined in the claims. The invention is defined by the
following claims, with equivalents of the claims to be included
therein.
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